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In this work we study the Double Exchange-Holstein (DE-H) model with an electron-phonon interaction $gamma$ coupled to magnetism. The analysis is performed combining a mean-field approximation for the double exchange interaction and the Lang-Firsov transformation for the electron-phonon interaction. Discontinuous magnetic transitions appear when the dependence of $g$ with $m$ is sufficiently large, resembling those experimentally observed in manganites. We observe that the characteristic resistivity peak that arises near the critical temperature appears for broad ranges of the system parameter values, unlike what occurs in a constant--$gamma$ model.
Establishing the physical mechanism governing exchange interactions is fundamental for exploring exotic phases such as the quantum spin liquids (QSLs) in real materials. In this work, we address exchange interactions in Sr2CuTe$_{1-x}$W$_{x}$O, a ser
The ability to tune exchange (magnetic) interactions between 3d transition metals in perovskite structures has proven to be a powerful route to discovery of novel properties. Here we demonstrate that the introduction of 3d-5d exchange pathways in dou
The double exchange model describing interactions of itinerant electrons with localized spins is usually used to explain ferromagnetism in metals. We show that for a variety of crystal lattices of different dimensionalities and for a wide range of mo
We study the ground-state properties of the double-chain Hubbard model coupled with ferromagnetic exchange interaction by using the weak-coupling theory, density-matrix renormalization group technique, and Lanczos exact-diagonalization method. We det
We study ground state properties of the double-exchange model on triangle chain in the classical limit on $t_{2g}$ spins. The ground state is determined by a competition among the kinetic energy of the $e_g$ electron, the antiferromagnetic exchange e